The present invention relates to systems and methods for use in spinal surgery, and in particular, relates to an implant system that allows for distraction, compression and fixation of vertebral bodies.
An example of spinal surgery is spinal fusion. Spinal fusion is a procedure that may be a solution to severe or debilitating back pain, instability stemming from spinal disorders such as herniated or torn intervertebral discs, spondylolisthesis (e.g., where the vertebrae move out of position), or degenerative disc disease. Interbody fusion, specifically in the lumbar region, can be performed using a variety of approaches including posterior lumbar interbody fusion (“PLIF”), transforaminal lumbar interbody fusion (“TLIF”), lateral lumbar interbody fusion (“LLIF”), or anterior lumbar interbody fusion (“ALIF”).
These lumbar interbody fusion procedures involve the removal of at least a portion of an intervertebral disc from the lumbar section of the spinal column, followed by fusion of the vertebrae that sit above and below the intervertebral disc. Typically, such fusion procedures involve the use of interbody implants (i.e., interbody fusion) and connected posterior structures. Fusion is achieved by distracting the vertebrae and inserting an intervertebral implant typically containing bone graft material into the space created by the removal of the intervertebral disc. Once the intervertebral implant is properly placed, the vertebrae may be compressed against it. Pedicle screws and rods may be used as an adjunct to interbody fusion to restrict the motion of the vertebrae while fusion takes place, to aid in setting the desired angle of lordosis, and to provide further fixation of the vertebrae.
Certain instruments exist that are used for distracting the vertebrae such as a pedicle or lamina distractors, for example. Other instruments exist that are used for compression of the vertebral bodies. Some instruments both distract and compress. However, these currently existing distraction and compression instruments are external instruments that are separate and apart from supplemental fixation devices, such as the above-noted pedicle screws and rods. Thus, multiple sets of instruments must be used for one procedure increasing the possibility of operating room confusion. Further, multiple instruments to achieve compression, distraction, and fixation increases the length of the interbody fusion procedure, which increases the probability for complications and may increase recovery time.
Therefore, there is a need for an internal fixation system that also acts as a distraction and compression device while utilizing only one set of instruments.